I read the China Study one day about 5 years ago, and didn't eat a single meat product for the ensuing six months. I was amazed how easy it was, once you put your mind to it (My wife joined me for most, but not all of it, especially since I do most of the cooking). We've subsequently gotten more relaxed about it, especially now that we're living aboard and it's not always easy to always have fresh veggies and the like. But we eat a lot less meat than we used to. In addition to the meat, cutting back on sugar, processed food and the like allegedly helps a lot.

There are a lot of good websites that can help you find some recipes to try - Vegetarian Times being one that you don't have to pay for to access.